Negative Differential Resistance and Shapiro Steps in a Superconducting MoN Strip with a Cut

Abstract

Regions with a negative differential resistance have been revealed in the voltage–current characteristics of superconducting MoN strips with a side cut under high-power microwave irradiation. A region with the negative differential resistance in the voltage–current characteristic is adjacent to steps, which are particularly pronounced at a low power of microwave radiation and are similar to Shapiro steps in the Josephson junction. The analysis within the time-dependent Ginzburg–Landau and heat conduction equations for the electron temperature has shown that the negative differential resistance is possibly due to the disordered (chaotic) motion of vortices across the strip near the cut, which occurs at a high microwave power.